================================================================== EXT4-fs (sda1): re-mounted. Opts: noblock_validity, BUG: KASAN: use-after-free in ext4_data_block_valid+0x276/0x2d0 fs/ext4/block_validity.c:211 Read of size 8 at addr ffff8801d5917590 by task syz-executor1/8297 CPU: 0 PID: 8297 Comm: syz-executor1 Not tainted 4.14.75+ #18 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 print_address_description+0x60/0x22b mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409 ext4_data_block_valid+0x276/0x2d0 fs/ext4/block_validity.c:211 ext4_mb_mark_diskspace_used+0x491/0x1370 fs/ext4/mballoc.c:3000 ext4_mb_new_blocks+0x900/0x39a0 fs/ext4/mballoc.c:4590 ext4_alloc_branch fs/ext4/indirect.c:335 [inline] ext4_ind_map_blocks+0x1021/0x2100 fs/ext4/indirect.c:619 ext4_map_blocks+0xafe/0x1560 fs/ext4/inode.c:638 _ext4_get_block+0x18d/0x490 fs/ext4/inode.c:783 ext4_get_block_trans+0x159/0x250 fs/ext4/inode.c:844 ext4_dio_get_block+0x6c/0xc0 fs/ext4/inode.c:861 get_more_blocks fs/direct-io.c:695 [inline] do_direct_IO fs/direct-io.c:980 [inline] do_blockdev_direct_IO fs/direct-io.c:1313 [inline] __blockdev_direct_IO+0x2b39/0xc4e0 fs/direct-io.c:1399 ext4_direct_IO_write fs/ext4/inode.c:3710 [inline] ext4_direct_IO+0x905/0x27f0 fs/ext4/inode.c:3863 generic_file_direct_write+0x225/0x430 mm/filemap.c:2940 __generic_file_write_iter+0x213/0x540 mm/filemap.c:3119 ext4_file_write_iter+0x4f6/0xe20 fs/ext4/file.c:264 call_write_iter include/linux/fs.h:1782 [inline] do_iter_readv_writev+0x3a4/0x560 fs/read_write.c:678 do_iter_write+0x156/0x530 fs/read_write.c:957 vfs_iter_write+0x70/0xa0 fs/read_write.c:970 iter_file_splice_write+0x5b4/0xab0 fs/splice.c:749 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x116/0x160 fs/splice.c:1018 splice_direct_to_actor+0x28c/0x750 fs/splice.c:973 do_splice_direct+0x17b/0x220 fs/splice.c:1061 do_sendfile+0x4a1/0xb50 fs/read_write.c:1438 SYSC_sendfile64 fs/read_write.c:1493 [inline] SyS_sendfile64+0xab/0x140 fs/read_write.c:1485 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457569 RSP: 002b:00007fbcd9f91c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000020000040 RSI: 0000000000000009 RDI: 000000000000000a RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000100000001 R11: 0000000000000246 R12: 00007fbcd9f926d4 R13: 00000000004c34d0 R14: 00000000004d5298 R15: 00000000ffffffff Allocated by task 1: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc_node mm/slub.c:2723 [inline] slab_alloc mm/slub.c:2731 [inline] kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736 add_system_zone+0x261/0x4d0 fs/ext4/block_validity.c:85 ext4_setup_system_zone+0x253/0x470 fs/ext4/block_validity.c:160 ext4_fill_super+0x706c/0xb5f0 fs/ext4/super.c:4291 mount_bdev+0x2ab/0x370 fs/super.c:1149 mount_fs+0x28f/0x31a fs/super.c:1255 vfs_kern_mount.part.9+0xce/0x4a0 fs/namespace.c:1057 vfs_kern_mount fs/namespace.c:1039 [inline] do_new_mount fs/namespace.c:2562 [inline] do_mount+0x404/0x26e0 fs/namespace.c:2892 SYSC_mount fs/namespace.c:3108 [inline] SyS_mount+0xe5/0x100 fs/namespace.c:3085 do_mount_root init/do_mounts.c:366 [inline] mount_block_root+0x378/0x727 init/do_mounts.c:395 prepare_namespace+0x1cf/0x20a init/do_mounts.c:600 kernel_init_freeable+0x382/0x39f init/main.c:1091 kernel_init+0xc/0x157 init/main.c:1000 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Freed by task 8304: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:524 slab_free_hook mm/slub.c:1389 [inline] slab_free_freelist_hook mm/slub.c:1410 [inline] slab_free mm/slub.c:2966 [inline] kmem_cache_free+0x12d/0x350 mm/slub.c:2988 ext4_release_system_zone+0x79/0x110 fs/ext4/block_validity.c:187 ext4_setup_system_zone+0x3a4/0x470 fs/ext4/block_validity.c:151 ext4_remount+0xdc2/0x1c60 fs/ext4/super.c:5237 do_remount_sb2+0x2eb/0x5f0 fs/super.c:878 do_remount fs/namespace.c:2377 [inline] do_mount+0xfae/0x26e0 fs/namespace.c:2883 SYSC_mount fs/namespace.c:3108 [inline] SyS_mount+0xe5/0x100 fs/namespace.c:3085 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff8801d5917578 which belongs to the cache ext4_system_zone of size 40 The buggy address is located 24 bytes inside of 40-byte region [ffff8801d5917578, ffff8801d59175a0) The buggy address belongs to the page: page:ffffea00075645c0 count:1 mapcount:0 mapping: (null) index:0xffff8801d5917b60 flags: 0x4000000000000100(slab) raw: 4000000000000100 0000000000000000 ffff8801d5917b60 0000000180490019 raw: dead000000000100 dead000000000200 ffff8801d907c200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d5917480: fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc ffff8801d5917500: fc fb fb fb fb fb fc fc fb fb fb fb fb fc fc fb >ffff8801d5917580: fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb ^ ffff8801d5917600: fb fb fc fc fb fb fb fb fb fc fc fb fb fb fb fb ffff8801d5917680: fc fc fb fb fb fb fb fc fc fb fb fb fb fb fc fc ==================================================================